Lumber bunching machine



T. E. COFFMAN LUMBER BUNCHING MACHINE June 22, 1954 Filed Dec. 26, 1951 2 Sheets-Sheet l //\///E/\/7'7F THOMAS E. COF-F-MAN E ak M .477-7-U =/\/& K5

Patented June 22, 1954 means UNITED STATEd @ATENT OFFICE 13 Claims.

This invention relatesto a machine-for bunching lumber to facilitate the manual handling thereof.

Some sawmills specialize in the production of oneparticular size of lumber, such as 2 inch by 4 inch by 8 foot studding, making it advantageous toutilize special purpose equipment designed for the standardized product. The general object of the present invention is to provide apparatus to facilitate the handling of such lumber, particularly'for shipment, as in the loading of railway cars and other means of conveyance. Heretofore, it has been the practice topick up the pieces directly from a delivery conveyor which discharges the boards from the mill, one after another. The boards arrive with sufficient rapidity to make it difficult to grasp several at a time and remove them from the path of the oncoming boards withoutzdanger of injury. The hazard and general awkwardness of this phase of the loading opera- 1 tion results in inefiicient and excessive costs relative to the primary mill operations.

Further and more specific objects of the invention are therefore to provide a bunching n1achine to receive therandom delivery and group the boards in small bunches, such as pairs, for convenient manual pick-up, and to provide a machine to accumulate a predetermined number ofboards and then deliverthem in pairs simultaneously to a pick-up station removed from the pointof accumulation and not. subject to the hazards and congestion of the delivery conveyor from the mill.

The mechanism of the inventionis mounted on a frame adjacent the end of a conveyor to receive boards being conveyed edgewise in a fiat position as from a sawmill. A plurality of rollers form an acoumulating platform to receive a predetermined number of the boards, such as four. When the platform is filled, one end is automatically released to fall by gravity. 'Mounted on the frame are a plurality of stationary upstanding tumblers. arranged in the path of fall of the boards when the platformis released to turn the boards on edge and placethem in pairs faceto face. Another conveyor then receives the boards to carry them away from the machine in pairs for manual pick-up.

The invention will be better understood and additional objects andadvantages will become apparent from the following description taken in connection with the accompanying drawings, which illustrate a preferred form of the device. It is to be understood, however, that the inven tion may take other forms, and that all such modifications and variations, within the scope of the appended claims, which will occur to persons skilled in the art, are included in the invention.

In the drawings:

Figure 1 is a side. elevation view of the invention showing a board supported on the platform of the machine;

Figure 2 is a view similar to Figure l but showing the platform in lowered position and the board turned on edge;

Figure 3 is a top plan view;

Figure 4 is an enlarged sectional view taken on the line 4% of Figure 3 showing the board turnblers, certain parts being eliminated to clearly s low said tumblers; and

Figure 5 is a schematic wiring diagram showing the electrical system for the machine.

The illustrated embodiment of the invention discloses the turning and discharging of boards it on edge, in pairs in face to face relation. Referring first to Figure 1, the mechanism is supported by a frame having legs H and i2 and horizontal members it. The frame is mounted at the end of conveyor belts l4, Figures 3 and 4-,

which pass over end pulleys it, one pulley l5 being shown in Figure 4. The belts I' l convey boards It one after another in random. spacing from a mill into the present mechanism.

Mounted on the legs I l at one end of the frame is a plate 20 secured thereto by bolts 2i, and mounted on the upper edge of said plate are a plurality of short axles 22 carrying pairs of rollers Zion each side of the plate iii. A trans verse shaft Ed is journaled in end bearings 25 above the legs I2 and carries a pair of arms 27, one on each side of the frame. Extending between the ends of the arms 2? is a bar 28 parallel with the plate 26 provided with a plurality of rollers 29 mounted on short axles 38, this set of rollers being horizontally aligned with the rollers 23 to form a platform or, with short rollers as shown, a pair of rests for boards to be received from the conveyor hi. Secured to the shaft 24 is a latch arm 3! which rotates with the shaft 24 and. arms 27.

A rod 32 extends upwardly on one side of the frame and a tension spring 33 is secured between the top of the rod 32 and one of the arms 2?, tending at all times to lift the arms to their Figure 1 position. The spring 33 is sufficiently strong to pivot the arms to their Figure 1 position when no boards are resting on the rollers 23 and 28, but when a load is received from the conveyor it, the weight of the boards overcomes the tension of the spring, and the arms tend to move to their Figure 2 position.

A latch bar 34 is pivotally mounted on the frame at 35 and has a catch 39 with a vertical surface thereon for engaging the latch arm 31. A tension spring 31 holds the bar 34 up in firm engagement with a stop 38, and as shown in Figure 1 the catch 95 has an inclined back surface so that the latch arm 3| will depress the bar 34 and slide over the catch 35, hooking itself behind the vertical surface thereof when the arms 21 are lifted by spring 33. Mounted beneath the latch bar 94 is a solenoid 39 having a link 4iirconnected between the armature of the solenoid and the bar 34. When the solenoid is energized, and a load of boards is on the platform, the rod 49 will pull downwardly on the bar 31! and release the latch arm 3i from behind the catch 35, whereby the arms 2'! pivot to the position shown in Figure 2 under the weight or the boards. The energization of the solenoid 39 is controlled primarily by a switch 4! having a switch finger 62 extending into the path of movement or the boards when loading the platform, so that when a board engages the finger 42 electrical current is supplied to energize solenoid 39. The electrical control system will presently be described in detail. Latch arm 3! is thus released to allow the shaft 24 and arms 21 to rotate and lower one end of the boards supported on rollers 29.

The movement of boards coming off the conveyor belts l4 and onto the rollers 23 and 29 is interrupted at such time by a pair of dogs 45,

Figures 3 and 4, which are operated by solenoids I 46. Compression springs 49 move the dogs 45 to disengaged position when the solenoids are deenergized. As seen in Figure 4, a board it has been engaged by the dogs 45 to hold back the following boards on belts l4 until the platform is returned to loading position. The continuously moving belts l4 slide freely under the boards l when they are so held.

Referring now to the mechanism for turning the boards on edge and conveying them in pairs away from the mechanism, I 9a resting on the rollers 29 and also boards lllb turned on edge. The two positions of the boards are merely illustrative, because operation of the machine is such that boards Hla are not present on the rollers while other boards lob are still in the machine. To turn the boards on edge there is provided a central tumbler 52 and two side tumblers 53 and 54. The central tumbler has a base portion 55 with apertures to receive upstanding rods 56. rods 56 and having apertures to receive the rods, is a pointed head 51 having inclined surfaces provided with serrations 58. Vertical rolls 59 are rotatably mounted on the rods 56 and protrude slightly beyond the head and base of the tumbler. The side tumblers 53 and 54 are similarly constructed in that bases 69 support upright rods 8| which in turn support heads 62. The rods 6| have rollers 93 mounted thereon between the bases 99 and the heads 62. In the side tumblers 53 and 54, the heads have only one inclined edge, each of which is facedtoward the central tumbler.

As best seen in Figure 4, the present machine is designed to handle four boards at a time, although more tumblers may be added as desired to handle a greater number of boards. When the arms 2'! are released and they start to drop to their Figure 2 position, the pointed heads 51 and Figure 4 shows boards Mounted at the top of the 62 divide the boards into groups of two and tilt them on their edges, as shown.

Means are provided to convey the boards away in their edgewise position which comprise a live roll 68 and a plurality of idle rolls 69 mounted on the frame of the machine, best seen in Figures 1 and 2. The live roll 68 has a pulley 19 on one end which is driven by an electric motor ll through belt 12. The idle rolls 69 are mounted on an inclined plane, and the boards are discharged from the machine thereon, the live roll 68 giving the boards a start down the rolls. The rolls 56 and 53 on the three tumblers are adapted to turn freely on the rods 56 and BI, respectively, to minimize rubbing friction of the boards against the sides of the tumblers as they leave the machine. The rollers 29 preferably have rounded corners to minimize retarding friction against the bottom of boards 3b in Figure 2. A suitable stop may be provided at the foot of the incline to hold the bunched lumber for convenient manual pick-up. v

As shown in Figures 1, 2 and. 5, a switch 8| has a switch finger 82 adapted to be engaged by one of the arms 21, and this switch is connected in circuit with the solenoids 49 so that whenever the arms 2! move away from the switch, the solenoids 46 are energized, lifting the dogs and preventing lumber from being conveyed onto the platform rollers 23 and 29.

With reference to the wiring diagram of Figure 5, power is supplied through a pair of line wires 85 and 86 having a main switch 81. Motor H is energized by a pair of leads 38 and 89, the motor running continuously as long as the switch 87 is closed.

Switch BI is a single pole double throw switch having two contacts 99 and 9| connected with the respective wires 92 and 93, the movable switch arm being connected to a wire 94. Switch M is connected in parallel with switch arm BI and contact 9 l, the Wire 93 being connected with line wire 85. For convenience, the numerals designating the switches generally in Figure l have been applied to the respective switch arm elements in Figure 5.

Switch 4| and wire 94 are also connected to a wire 95 leading to the solenoids 46 on the dogs 45. Wires 95 and 9'! connect these solenoids with the other line wire 86. Solenoid 39 for latch bar 34 is connected to wires 91 and 92, this circuit being completed through switches BI and 4! and wires 94 and 93 at one phase of operation.

The normal positions of switches 4i and BI are as shown in Figure 5 deenergizing solenoids 39 and 46. The dogs 45 are thereby depressed by springs 49, and the platform comprising rollers 23 and 29 is in position to receive the first board in from the conveyor belts M, the arms 21 being latched in elevated position by the engagement of latch bar 34 with latch arm 3|. Switch arm 8| is held in engagement with contact by one of the arms 21 as shown in Figure 1.

To prevent the first board from coasting across the platform by momentum and prematurely engaging switch finger 42 and closing switch 41. one or both sets of the rollers 23, 29 may be inclined upwardly to arrest the motion of the boards after they leave the belts M. In the present embodiment, however, the platform comprising rollers 23 and 29 is horizontal, and the movement of one end of the first board is arrestedby a fixed stop I99, Figure 3. The other end of the first board strikes a ballistic retarder or arrester [9| comprising a heavy pendulous bar preferably pivotally suspended at its upper end by a chain or link, to intercept the board and absorb its impulse energy before the board can engage switch-finger 42.

Bar l0! acts as a ballistic pendulum, arresting the advancingmovement of the first board before the bar is deflected an appreciable amount, the kinetic energy of the board being instantaneously transferred to the bar, leaving the board substantially stationary. boards will bump into the first board and transmit their impact energy therethrough to the ballistic arrester Hll without moving the first board into engagement with switch finger 42. Thus, the platform becomes loaded with the four boards Illa without prematurely actuating the switch 4 l.

The platform now being filled, the fifth board arrives and exerts a steady push against the platform load by reason of the constant driving efiort exerted by the moving belts M- engaging the under surface of the fifth board trying to carry it forward. The ballistic arrester llll responds freely to a steady force, allowing the four boards Illa to be pushed forward until the leading board engages switch finger 42 to close switch 4! as shown in Figure 4.

The closing of switch 4| completes a circuit through wires 93, 94, switch 8!, wire 92, solenoid 39 and wire 9?, to retract the latch bar 34 and allow bar 28 and rollers 29 to fall. A parallel circuit is simultaneously completed through wire 93, switch 4|, wire 95, solenoids .15 and wires 95 and 91, to lift the dogs 45 into engagement with the fifth board to prevent its advance onto the platform. As the arms 2! drop under the weight of boards llla, the first board leaves its engagement with finger 42 causing switch ll to return to its normally open position. Arm 2? leaves its engagement with finger 82 causing switch arm 8! to leave contact 50 and engage contact 9!. The

circuit to solenoid 39 is thereby broken, but the circuit through solenoids 46 is restored around switch 4| through wire 94, switch 8! and contact 9| before the dogs 45 have time to release the fifth board, and said board is not permitted to be advanced at this time.

As the four boards engage the tumblers 52, 53 and 54 in dropping, they are tilted on edge in pairs as indicated at [0b in Figure t, and discharged from the machine on rolls 63 and 69, as

shown in Figure 2. As soon as the trailing edges of the four boards [0b have cleared the rollers 29, spring 3-3 raises these rollers back to their Figure 1 position, causing one of the arms 27 to engage switch finger 82 and return switch arm 8| back to engagement with contact 95. This switching operation deenergizes solenoids 46, allowing springs 45 to drop the dogs '25 and allow the fifth board temporarily engaged thereby to advance onto the platform rollers 23 and 29. The upward movement of arms 21 engages latch arm 3| with latch bar 34 before the fifth board has time to move onto the platform rollers 29. This operation completes the cycle, switches fl! and SI being returned to their Figure 5 position and solenoids 39 and 46 being deenergized. The cycle repeats automatically as long as boards are supplied by belts l l.

The platform may be extended and additional tumblers provided to accommodate six or eight, or more, boards, in order to bunch a correspondingly greater number of pairs, but the present arrangement is advantageous for two loader workmen stationed to take the boards from the rolls 69, or suitable conveyor means in continuation Subsequently, the following thereof. In the present machine, two pairs of boards are delivered on the rolls 69 in each cycle of operation, making it convenient for two loaders to pick them up in pairs for manual placement in the intended transportation facility. While this manual operation is being performed, the machine delivers two more pairs of boards which are presented in convenient position to be picked up by the time the loaders are ready for them. Thus, the machine bunches the boards in pairs, which is the most convenient size of load of eight foot two by fours and the like for a workman to pick up and carry away quickly for manual placement. The workmen are relieved of the effort of the bunching operation, and do not have to dodge the oncoming boards to avoid injury to their hands in picking up each pair. Their objects of the invention arethereby accomplished in a relatively simple and inexpensive machine, which greatly reduces the manual effort required in handling large quantities of standardised pieces of lumber such as studding.

Having now described my invention and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is:

1. A lumber bunching machine comprising means to support a plurality of boards in edge abutting relation, means to divide said plurality of boards into groups of two and turn said boards on edge, and means to convey said boards from the machine in longitudinal movement supported on edge.

2. A lumber bunching machine comprising means for supporting boards in edge abutting relation, a plurality of upstanding pointed tumblers spaced two board widths apart beneath the boards on said supporting means, and means for producing relative vertical movement between said tumblers and supporting means to separate the boards in pairs and turn them on edge.

3. A lumber bunching machine comprising rest means for supporting the ends of boards disposed in edge abutting relation, means for lowering said rest means under one end of the supporting boards, upstanding tapered members below said rest means, said members engaging said boards when said rest means is lowered to separate and turn said boards on edge, and means to convey said boards from the machine in edgewise position.

4. A lumber bunching machine comprising rest means for supporting the ends of boards disposed in edge abutting relation, means for lowering said rest means under one end of the supported boards, upstanding tapered members mounted below said rest means, said members being arranged to turn said boards on edge and group said boards in pairs when said rest means is lowered to engage the boards with said members, and rolls extending between said members to carry said boards in edgewise position from the machine.

5. A lumber bunching machine comprising support means having a level loading and inclined unloading position for boards-a series of inclined rolls to receive said boards in unloading position of said support means, and stationary tumbler elements arranged to engage the boards in the unloading position of said support means to turn the boards on edge on said inclined rolls.

6. A lumber bunching machine comprising a frame, means on said frame to support a predetermined number of boards, said means having one end arranged to be lowered by gravity, means to automatically release said end of said supporting means when said predetermined number of L. 2" boards is disposed on said supporting means, and a plurality of upstanding stationary tumblers engageable with the boards when said one end is lowered, to separate and turn the boards on edge.

7. A lumber bunching machine comprising two series of rollers forming a support for horizontal boards, a plurality of upstanding tumblers mounted below said support, and means to lower one of said series of rollers to engage said boards with said tumblers to turn the boards on edge and group them in pairs.

8. A lumber bunching machine comprising a support having spaced rests to hold a predetermined number of boards, one of said rests adap ed to be lowered by gravity, means mounted beneath said support to separate and turn said boards on edge when said one rest is lowered, means to automatically release said one rest when said predetermined number of boards is placed on the support, and means to prevent operation of said release means by less than said predetermined number of boards.

9. A machine for bunching boards received from a conveyor and the like, comprising means adjacent said conveyor to stop the travel of boards into said machine, releasable supporting means for receiving a predetermined number of boards, means to automatically release said supporting means when said predetermined number of boards has been received, means mounted beneath said supporting means to turn said boards on edge when said supporting means is released, and means to actuate said stop means to stop the travel of boards onto said supporting means when said holding means is released.

10. A machine for bunching boards comprising a frame, a series of rollers on one end of said frame, a series of rollers on the other end of said frame, said two series of rollers being arranged to support boards in horizontal position, one of said series of rollers being mounted for vertical movement, and a plurality of upstanding members mounted below said rollers and having sloping surfaces to turn said boards on edge and group them in pairs when said one series of rollers is lowered relative to said members.

11. A machine for bunching boards comprising means to support a predetermined number of boards side by side in flat position, means to automatically lower one end of said boards when said predetermined number of boards is disposed on said supporting means, and a plurality of upright tumblers having pointed ends disposed approximately two board widths apart to project between the boards and turn them on edge when said one end of the boards is lowered.

12. A machine for bunching boards comprising a board supporting rest mounted for gravity movement from a loading position to an unloading position, a latch to hold said rest in loading position, means extending into the path of said boards in fully loaded position on said rest to release said latch, means to stop a moving board before it engages said release means but yieldable under steady pressure to permit said engagement, and a plurality of upstanding tumblers beneath said rest to engage the boards and turn them on edge when said rest moves to unloading position.

13. In a lumber bunching machine and the like, a rest mounted for gravity movement from a loading position to an unloading position to discharge a load of boards therefrom by gravity, means to advance boards onto said rest in edgewise movement, a ballistic retarder in the patch of advancing boards on said rest to absorb the impulse energy of a moving board and sto said board, said retarder being freely yieldable to steady pressure of the boards when the rest is fully loaded, and. means engageable by the leading board on the rest to'release the rest for movement to said unloading position when said retarder has yielded under steady pressure.

Name Date George July 19, 1904 Number 

